The red-hot Dallas Cowboys rookie quarterback, who will face perhaps his toughest test yet Thursday night in Minneapolis against a potent Minnesota Vikings defense, has exploded onto the pro scene. He’s been in good hands, getting coached up by Dallas' Jason Garrett and position coach Wade Wilson, both former NFL quarterbacks, along with coordinator Scott Linehan.

But Mullen, whose program was ranked No. 1 for a few weeks in 2014 with Prescott as the spark, has to feel so invested in the NFL’s biggest surprise. With Prescott rolling amid a high-powered supporting cast, including another sensational rookie in tailback Ezekiel Elliott, the Cowboys (10-1) have the league's best record, and Tony Romo couldn’t get his job back after healing from a preseason back injury.

“I’m not surprised by what he’s doing,” Mullen insists. “He was prepared for this. Even though we’re a spread team, we run a lot of pro concepts with our passing game and protections and responsibilities. And he developed more every single year.”

It’s one thing that Prescott, whose 108.6 passer rating ranks fourth in the NFL and would be a rookie record if it holds up, is flourishing as a fourth-round pick. A lot of teams whiffed in the evaluation process, with accuracy among the knocks on Prescott, who's completing nearly 68% of his passes. Even the lucky Cowboys first attempted moves to draft Paxton Lynch and Connor Cook.

Yet as Mullen noted, Prescott, who rushed for more than 1,800 yards during his first two years as the Bulldogs' starter, has adapted quickly despite his spread background and those dubious scouting reports. Jared Goff, drafted first overall by the Los Angeles Rams, played in a spread offense at Cal, and coach Jeff Fisher didn’t deem him ready to play until Week 11.

During the summer, Prescott told USA TODAY Sports’ Lorenzo Reyes: “The offense we ran at Mississippi State was nothing short of an NFL offense. The only thing that was different is that we didn’t go under center. I swear to you, in (pre-draft) visits, every play they showed me, I could name it.”

No, not all spread offenses are created equally. Prescott’s hard work in his college system, which was more complex than most, helped him jump right into Dallas' playbook — to the point that Garrett and Co. maintain that they haven’t had to “dummy down” their scheme as many are forced to do with a rookie quarterback.

Mullen said that his scheme dictated that Prescott had five reads in his passing progression, which can equate to “whole-field” reads in the NFL, and the responsibility of choosing from roughly 15 different offensive-line protections. Prescott started for three years in college, and progressively earned more freedom to switch plays at the line of scrimmage.

“All of those things combined,” Mullen said, “add up to stuff he’s asked to do at the next level.”

Also significant? Last year, while in grad school after earning his bachelor’s degree in (fittingly) information systems, Prescott joined Mullen and his staff for meetings early in the week to devise the game plan. That strengthened his grasp of Mullen's offensive concepts and how different types of plays connect and work against defenses in the big picture of a game plan. That background has helped Prescott demonstrate a knack with the Cowboys for deciphering defenses better within games as they unfold.

"When you understand the whys ... it’s easier to make adjustments during the game,” Mullen said. “When the defense shows a certain coverage on third-and-4, it’s going to all make sense.”

Despite running his offense from the shotgun formation, Mullen mandated extensive work during the offseason on taking snaps. So while Prescott didn’t work under center during games — there are some quarterbacks who reach the NFL without ever taking a snap on the high school or college levels — the notion of a snap exchange wasn’t exactly foreign to him when he arrived in Dallas because of Mullen's spring program.

“I’ve always forced my quarterbacks to do those drills,” said Mullen, who coached Alex Smith, Tim Tebow and Cam Newton before landing at Mississippi State. “It teaches you better balance, footwork and body control. It’s not a culture shock when they get to the NFL, because they’ve practiced it.”